To hunt down the most heartless of killers, investigators must carefully gather clues to build an accurate profile, and there's always traces of the fiend somewhere left behind.
When a young woman is found shot to death near an Alaskan village, detectives rely on forensic science to catch her murderer; then an eyewitness comes forward with an explosive revelation that threatens to tear apart the small town.
In Flint, Mich., an 80-year-old woman is murdered while running errands; investigators tie her case to an unsolved drive-by shooting and must use science and skillful interrogation to catch a remorseless killer.
In the late 1980s, an elusive serial killer stalks the streets of South Central Los Angeles, raping, murdering and discarding his victims; two decades later, clever police work and new technology put an end to The Grim Sleeper's reign of terror.
When a little girl disappears from a small Washington town over a Fourth of July weekend, detectives look at suspects close to home; then her body is found two weeks later, and a tip leads investigators to a trusted friend with a terrifying past.
When a New Jersey mother is raped and murdered, her sadistic killer leaves no trace of his identity behind; months later, a violent attack in another state gives detectives the evidence they need to put her killer away for good.